totp-ssh-fluxer dynamically alters the SSH port at regular intervals using Time-based One-time Passwords (TOTP). It aims to increase the difficulty of automated login attempts. The core functionality revolves around generating TOTP tokens and using their digits to redirect incoming SSH connections through iptables rules, effectively fluxing the listened port.
This project uniquely leverages TOTP codes, normally used for two-factor authentication, to control SSH port redirection. The implementation uses iptables PREROUTING rules to maintain established connections even after TOTP token expiration. Its simplicity lies in the straightforward loop that generates tokens, redirects connections, and removes rules.
- Port Fluxing: Dynamically changes the SSH port every 30 seconds.
- TOTP Integration: Uses TOTP codes as the source for port redirection.
- iptables PREROUTING: Maintains established connections during port changes.
- Simple Implementation: A single Go file for ease of understanding.
- Root Privileges: Requires root privileges for iptables manipulation.
The project is currently very basic, consisting of a single Go file, and was created as a demonstration concept. Documentation is minimal, with instructions primarily found in the linked totp-ssh-flux project. Maintenance activity is infrequent, and long-term reliability has not been established.
totp-ssh-fluxer is intended for security researchers and those interested in unconventional security measures. It provides a unique, though potentially unreliable, method for hindering automated SSH brute-force attacks. It differs from standard SSH hardening by employing TOTP for dynamic port changes, adding a layer of obscurity beyond typical port changes.